PDP-11 architecture Was: internet blocking problem ?

[Paul Koning]

> On Sep 11, 2015, at 11:23 AM, Warner Losh <imp at bsdimp.com> wrote:
> 
> On Fri, Sep 11, 2015 at 9:03 AM, Paul Koning <paulkoning at comcast.net> wrote:
> 
>> ...
>> For efficient overlays, RT-11 with Link tends to be better.  It's less
>> flexible but that reduced flexibility enforces more care in overlay design,
>> and the implementation is a whole lot faster.
> 
> 
> True. We were running under RSTS-E and so had some more flexibility.
> However, by the time we got to this overlay structure, we knew we'd done
> something horribly wrong and spent several weeks slimming down the program,
> reducing the number of parameters to some routines and redesigning some
> code to have either simpler algorithms, or inlining some code. We slimmed
> it by 30% but more importantly went from about 8 overlay depth to 3. Still
> slow, but it was acceptably slow rather than insane.

The nice thing about RSTS/E is that you can use either the RT11 or the RSX tools, according to which is the best answer for what you're doing.  And that gives you a choice of overlay schemes (regions with LINK, or trees with TKB).

	paul